1. Field of the Invention
This invention is in the field of attenuators.
2. Description of the Prior Art
Typical prior art rotary step attenuators utilize various spring-loaded contacts and combinations of contacts in order to provide electrical coupling between the cables leading to the attenuators and the attenuator pads mounted therein on a rotor. Such attenuators include, for example, those shown in U.S. Pat. No. 3,299,373 to Conney, No. 3,219,953 to Schwartz, No. 3,550,046 to Bacher, and No. 3,622,919 to Wilhoit. These spring biased contact assemblies are expensive to produce and are subject to mechanical failures in the assembly. A rotary step attenuator having a more direct contact method, though without providing contact to the attenuator elements themselves, is shown in U.S. Pat. No. 3,805,209 to Keranen. A direct contact attenuator, described as being for use from DC to above 8 GHz, lacking discrete attenuator elements but utilizing direct contact onto a resistive pad, is shown in U.S. Pat. No. 3,786,374 to Bergfried.